wireless hard drives?

so, i got a new macbook air from work. like the previous it has a 500 gb hard drive. unlike with the previous, i would like to not fill up the hard drive--with more than 400 gb of files, performance was less than optimal. the easiest way to achieve this would be to keep my music and images on a separate drive. but i'd rather not have to connect a cable to upload and download files. since i last purchased an external hard drive wireless drives seem to have become available. are they reliable? or should i be paying for cloud storage?

literally the only thing i need an external drive for is music. everything else is being backed up to crash plan at work. just need something to park 160 odd gigs of music on so my laptop keeps running as smoothly as it is now.

If you can't run iTunes over the cloud that's a reasonable to ditch apple

i could be wrong but i'm under the impression that a) itunes needs a physical library (or can you point it to a library in the cloud?) and b) that if i put my music library on the cloud i'd still need to download/rip new music to my machine, then upload to the cloud, then delete the files (to achieve my goal of not clogging the laptop's drive)--which seems a bit of a pain.

I don't know anything about iTunes but I do know that your odds of coming home to find that something in the unpatched ancient kernel running in that wifi nas has failed and you've got no music are about a hundred times better than with just a USB hard drive (which in turn is many times more likely to fail than an internal drive). Add to this the occasional driving of your laptop to a halt as a mounted filesystem is suddenly across wifi interruption and just don't do it.

sandwiches that are large and filling and do not contain tuna or prawns